1. Field of the Invention
The present invention relates to a composite device including a mounted component such as a chip component and a semiconductor module component, and a substrate in which the mounted component is mounted.
2. Description of the Related Art
When a mounted component such as a chip component and a semiconductor module component is mounted in a substrate such as a printed-circuit board, a conductive bonding material is usually used. In general, a terminal electrode of the mounted component is electrically and mechanically bonded to a land of the substrate with solder.
As the conductive bonding material, International Publication No. 2013/132942 discloses a Sn-Cu-Ni alloy-based material. When this conductive bonding material is used, heating at a level of 300° C. accelerates a change into an intermetallic compound having a high melting point of 400° C. or more, and consequently a low-melting point component does not remain. Therefore, for example, in a semiconductor device manufacturing process, after a semiconductor device is manufactured through a soldering step, even when the semiconductor device is mounted in a substrate by a reflow soldering method, a soldering part based on the conductive bonding material is superior in heat-resistant strength, and thus the soldering part is not re-melted in a reflow soldering step, enabling highly reliable mounting.
In recent years, mounted components are more and more miniaturized, and as a result, the size of the land on the substrate is also miniaturized to allow mounted components to be mounted thereon. Therefore, in a structure of mounting with solder, it is getting more difficult to sufficiently maintain the mechanical strength of mounted portions.